Skip to main content

Reply to this post | See parent post | Go Back
View Post [edit]

Poster: A/V Geek Skip Date: Nov 5, 2005 9:32am
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

Thanks for the feedback.

Below is another file to try. We've had one person with an iPod who's tried it and says that there are no audio problems.


Reply to this post
Reply [edit]

Poster: kc0dhb Date: Nov 5, 2005 2:49pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

That file worked quite nicely (little grainy, but sound was good).
Just out of curiousity, what did you change?

I also rewrote my script to allow for you to change the bit rate when you run the program.

I also found that 368kbps works very well for cartoons (color too)


Perl script follows
#Written by Kyle Byerly
#required software
# ffmpeg compiled with --enable-mp3lame --enabled-faad --enable-faac --enable-xvid buildflags
# instructions for ubuntu at
# the original script was one i took from iSquint for Mac, but since my Linux box is quite
# a bit faster than an aging powerbook...

print "When you execute this script, enter the files you want after the script on the commandline.\n";
print "Example.\n";
print "\t./ /home/kyle/dvd/*.avi\n";
print "This will place files with the exact same name with 2300kbps.ipod.mp4 appended to the filename, if 2300 was the bitrate\n";
print "Right now it only makes files optimized for the iPod screen\n";

print "Please enter the bitrate that you would like, less than 2500, default of 2300: ";
chomp($bitrate = );
#set default bitrate of 2300
if ($bitrate == "\n") {
$bitrate = 2300;
#if the bitrate is greater than 2500 you can still encode, but why?
if ($bitrate > "2500") {
print "This is greater than an iPod will play...just so you know.\n";
if ($bitrate < 256) {
print "Output may be ok, but not so good on fast moving parts...recommend you try a higher bitrate.\n"

foreach (@ARGV) {
system < ffmpeg -i "$_" -s 320x240 -vcodec xvid -g 300 -qmin 2 -b $bitrate -acodec aac -ar 44100 "$_"."$bitrate"kbps.ipod.mp4 >;

Reply to this post
Reply [edit]

Poster: A/V Geek Skip Date: Nov 5, 2005 11:58pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

The Internet Archive has been working on fixing the MPEG-4 derivation parameters, so I'm going back and re-deriving the older films to see if the audio squeak problem has been fixed.

So, if you and other iPod users could help verify that these files are fixed, I can start re-deriving all the feature films.

What was changed? I dunno. Tracey at the IA worked really hard to fix MPEG-4 transcoding parameters a couple of months ago.

Here's some files to check out:


Reply to this post
Reply [edit]

Poster: tracey pooh Date: Nov 6, 2005 2:26am
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

Yay! A new mp4 success on ipod, woot! 8-D

Yes, so we had an intern who brilliantly figured out how
to solve most of our audio problems by simply using
"mplayer" to dump the audio as a stereo WAV track.

Since mplayer can play pretty much anything, this meant
that most of our "audio problems" suddenly got fixed.
Better yet, instead of the 3-4 audio pass encodings just
to get the WAV/PCM format, it's all done in one quick
mplayer command now.

I then hooked it all up, fixed up some "encode to mpg audio"
settings, and there it is!

Lastly, I tossed 15 of the worst and most difficult items
I knew at it and rederived them (they had horrible or
completely gone audio in the derived mp4s). To my utter
shock and delight, all worked.

As I personally love moving images, I'm glad we finally got
a lot of this audio stuff fixed!
mp4 files aren't the easiest to "get right" -- they're not
like the supereasy MPG1 and MPG2 formats, unfortunately.

--tracey, webmaster,
and occassional movie geek and cheerleader

Reply to this post
Reply [edit]

Poster: Supersensor Date: Feb 20, 2006 2:10pm
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

I have also been having trouble with my iPod video in two ways, but maybe this will help:
1. Some films that I used iSquint to convert (I have grabbed some of the larger mpeg files that need conversion before they are dropped into iTunes,) and they have a flaw in that the video/audio will freeze, and then restart with no audio. Apparently this is a flaw with the iPod 1.1 updater.
2. Some of the 256k/Mp4 files will play fine in Quicktime or in iTunes, but on the iPod they produce a clicking/digi-distortion periodically. This may also be related to the updater issue, BUT, I had no trouble with the "Night of the Living Dead" mp4 file that was posted, so maybe that answers something. Also, as a pure side note, when I have ripped PD stuff from DVD (I use Mac, so Mac the Ripper is a nice option,) then convert to Mp4 with Handbrake it seems to work well. Just laying everything I know out there. Hopefully we can all help each other.

Reply to this post
Reply [edit]

Poster: kc0dhb Date: Nov 6, 2005 9:51am
Forum: movies Subject: Re: iPod + Video and Archive MPEG4 Files

fine (messed up movie...)
completely broken
Sound and Video both broken
audio dies near the end.